#!/usr/bin/perl -w
# -*- mode: cperl; coding: utf-8 -*-
# Most of this code was stolen from Debhelper 7.3.16+. which is:
# Joey Hess, GPL copyright 1997-2009.
# Adapted for CDBS purposes by Colin Walters <walters@debian.org>
# Copyright © 2010-2011, 2015-2016 Jonas Smedegaard <dr@jones.dk>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

sub error {
  my $err = shift;
  print STDERR $err;
  exit 1;
}

sub samearch {
	my $arch=shift;
	my @archlist=split(/\s+/,shift);

	foreach my $a (@archlist) {
		system("dpkg-architecture", "-a$arch", "-i$a") == 0 && return 1;
	}

	return 0;
}

sub buildarch {
	my $value=`dpkg-architecture -qDEB_HOST_ARCH` || error("dpkg-architecture failed: $!");
	chomp $value;
	return $value;
}

sub GetPackages {
	my $type=shift;

	$type="" if ! defined $type;

	my $package="";
	my $arch="";
	my @list=();
	my %seen;
	my @profiles=();
	my $included_in_build_profile;
	if (exists $ENV{'DEB_BUILD_PROFILES'}) {
		@profiles=split /\s+/, $ENV{'DEB_BUILD_PROFILES'};
	}
	open (CONTROL, 'debian/control') ||
		error("cannot read debian/control: $!\n");
	while (<CONTROL>) {
		chomp;
		s/\s+$//;
		if (/^Package:\s*(.*)/i) {
			$package=$1;
			# Detect duplicate package names in the same control file.
			if (! $seen{$package}) {
				$seen{$package}=1;
			}
			else {
				error("debian/control has a duplicate entry for $package");
			}
			$included_in_build_profile=1;
		}
		if (/^Architecture:\s*(.*)/i) {
			$arch=$1;
		}

		# rely on libdpkg-perl providing the parsing functions because
		# if we work on a package with a Build-Profiles field, then a
		# high enough version of dpkg-dev is needed anyways
		if (/^Build-Profiles:\s*(.*)/) {
				my $build_profiles=$1;
			eval {
				require Dpkg::BuildProfiles;
				my @restrictions=Dpkg::BuildProfiles::parse_build_profiles($build_profiles);
				if (@restrictions) {
					$included_in_build_profile=Dpkg::BuildProfiles::evaluate_restriction_formula(\@restrictions, \@profiles);
				}
			};
			if ($@) {
				error("The control file has a Build-Profiles field. Requires libdpkg-perl >= 1.17.14");
			}
		}

		if (!$_ or eof) { # end of stanza.
			if ($package && $included_in_build_profile &&
#			    (($type eq 'indep' && $arch eq 'all') ||
#			     ($type eq 'arch' && $arch ne 'all') ||
#			     ($type eq 'same' && (samearch(buildarch(), $arch))) ||
			    (($type eq 'indep' && $arch eq 'all') ||
			     ($type eq 'arch' && $arch ne 'all') ||
			     ($type eq 'same' && ($arch eq 'any' ||
					     ($arch ne 'all' &&
			                      samearch(buildarch(), $arch)))) ||
			     ! $type)) {
				push @list, $package;
				$package="";
				$arch="";
			}
		}
	}
	close CONTROL;

	return @list;
}

print join(' ', GetPackages($ARGV[0])) . "\n";